The Facts on Eating Disorders

More people are being diagnosed with eating disorders, possibly as a consequence of society's emphasis on and preoccupation with thinness. Eating disorders are conditions that involve genetic, biological, psychosocial, and environmental factors. In North America, anorexia nervosa,bulimia nervosa, and binge eating disorder are the most common eating disorders. More women than men are affected by eating disorders.

Anorexia nervosa is a psychiatric condition in which people restrict their food intake or use behaviours to prevent weight gain, because of an intense fear of becoming fat or obese. In reality, people affected by this condition are almost always underweight or of normal weight when the condition starts. This disorder usually starts in the years between adolescence and young adulthood, with the average age of onset at 18 years. Women are more affected by anorexia than men. Current statistics say that in their lifetimes, 9 in 1000 females and 3 in 1000 males will be diagnosed with anorexia. However, in 2013 the diagnostic criteria were modified to be less restrictive, and by this newer understanding, these numbers are an underestimation.

Bulimia nervosa is an eating disorder characterized by repeated and uncontrolled or compulsive binge eating, followed by inappropriate ways of trying to get rid of the food eaten. Most often, this involves purging by self-induced vomiting or abuse of laxatives, enemas, or diuretics. It's also sometimes called the "binge-purge syndrome." Some people with bulimia don't purge, but will binge-eat (consuming as many as 20,000 calories at one time) and then compensate for binge eating sessions with other behaviours such as fasting or over-exercising. A person with bulimia may secretly binge anywhere from once a week to several times a day.

Bulimia commonly appears in the latter part of adolescence or early adulthood, but it can develop at an earlier or later age. Like anorexia, the median age of onset for bulimia is 18 years. Bulimia also affects women more than men: about 3 times as many women as men will have it in their lifetimes.

Binge eating disorder is characterized by the same uncontrollable binge eating that is seen in bulimia nervosa, but without any purging behaviours after binge eating episodes. This condition is distinct from overeating or obesity. Previously, clinicians used the category “eating disorders not otherwise specified” to capture all eating disorders not meeting the criteria for anorexia nervosa or bulimia nervosa, but in 2013 binge eating disorder was recognized as a unique diagnosis.

Causes of Eating Disorders

Eating disorders are generally viewed as being psychological in origin. However, like depression, schizophrenia, and bipolar affective disorder, they are currently believed to have many causes, including genetic and functional changes in the brain. People suffering from anorexia and bulimia have preoccupations with body image, weight, and eating. They also have a distorted personal body image and a fear of fatness and weight gain.

Although cultural factors have an influence on the development of eating disorders, they appear to stem from multiple factors. There has been a lot of debate about the role of parenting and family environments in relation to eating disorders. Genetic and hormonal factors are believed to play significant roles; people with eating disorders are believed to have a genetic predisposition to the illness. Individuals who have a family history of depression, alcohol abuse, obesity, or eating disorders are at higher risks for anorexia nervosa and bulimia nervosa. There also appears to be a neurological relationship between patterns of eating (such as dieting and starvation) and the nervous and hormonal systems, since hunger, food cravings, and feelings of fullness are controlled by certain areas of the brain and involve a number of digestive hormones.

Symptoms and Complications of Eating Disorders

People with anorexia nervosa may appear severely emaciated due to malnutrition; sometimes their ribs can be seen through the skin. Other common symptoms of anorexia include:

constipation

dehydration

depression

dizziness

dry, scaly skin

hair loss

faintness or weakness

inability to concentrate

intolerance to cold

irritability

loss of body fat

low blood pressure

missed, or absence of, menstrual periods

psychological fears of obesity and weight gain

slow or irregular heartbeat

If the onset of anorexia occurs before puberty, a girl's sexual development will stop and menstruation won't begin. Severe anorexia leads to chronic malnutrition, which has damaging effects on the body, especially the bones, thyroid, heart, and digestive and reproductive systems. Anorexia can be fatal. Half of those who die with anorexia die of suicide, and the other half die of medical complications.

Some people with bulimia may experience episodic weight loss, while others maintain a normal weight or may even be overweight. In some cases, menstrual cycles may be affected and stopped, but menstruation is usually preserved. Possible symptoms of bulimia include:

dehydration (due to excessive use of laxatives or frequent self-induced vomiting)

tooth decay and erosion (due to the acids that are brought up from repeated self-induced vomiting)

low blood pressure

constipation

swollen saliva glands in the cheeks (like mumps)

abnormal hormone levels

stomach and esophagus problems

irregular heartbeat

A variety of complications can result from the constant vomiting. For example, inflammation of the esophagus (called esophagitis) and severe dental problems can occur. At its worst, constant purging can lead to heart damage. People with bulimia may have a history of anorexia or obesity. They may also have psychiatric problems such as depression, panic disorder, social phobias, and anxiety disorders, as well as addictive behaviours like alcohol or drug abuse.

Patients with binge eating disorder experience the same binge eating seen in those with bulimia nervosa, but do not have compensatory behaviours after binge eating. Some symptoms of binge eating disorder include:

eating more food within a period of time than most people in similar circumstances

feeling a lack of control over eating during an episode

eating until uncomfortably full or more rapidly than normal

eating large amounts of food when not hungry

eating alone or in secret because of embarrassment at how much one is eating

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